Stellar Question
For some reason, a combo of reading about the successful launch of Chandrayaan (Hurray, India!), & aveerah's entry, suddenly caused me to remember the following:
This is a beautiful incident regarding Wittgenstein (BTW, I'd love to know who your favorite philosopher is? He's mine! :)), that Richard Dawkins mentioned in one of his talks. I think some of you guys will enjoy it as well!
We are now so used to the idea that the Earth spins rather than the Sun moves across the sky. It’s hard for us to realize what a shattering mental revolution that must have been. After all it seems obvious that the Earth is large and motionless, the Sun small and mobile. But it is worth recalling Wittgenstein’s remark on the subject. “Tell me”, he asked a friend, “Why do people always say it was natural for man to assume that the Sun went around the Earth rather than that the Earth was rotating?” His friend replied, “Well obviously because it just looks as though the Sun is going around the Earth!” Wittgenstein replied, “Well what would it have looked like if it had looked as though the Earth was rotating?”
So kids, how do you know that it's the earth that's moving? Wanna guess?
Answer Below
One way is by observing that there's a Doppler shift of starlight. Here are other ways by which we can find out. Cute huh?
This is a beautiful incident regarding Wittgenstein (BTW, I'd love to know who your favorite philosopher is? He's mine! :)), that Richard Dawkins mentioned in one of his talks. I think some of you guys will enjoy it as well!
We are now so used to the idea that the Earth spins rather than the Sun moves across the sky. It’s hard for us to realize what a shattering mental revolution that must have been. After all it seems obvious that the Earth is large and motionless, the Sun small and mobile. But it is worth recalling Wittgenstein’s remark on the subject. “Tell me”, he asked a friend, “Why do people always say it was natural for man to assume that the Sun went around the Earth rather than that the Earth was rotating?” His friend replied, “Well obviously because it just looks as though the Sun is going around the Earth!” Wittgenstein replied, “Well what would it have looked like if it had looked as though the Earth was rotating?”
So kids, how do you know that it's the earth that's moving? Wanna guess?
Answer Below
One way is by observing that there's a Doppler shift of starlight. Here are other ways by which we can find out. Cute huh?